As a conventional optical transmitting and receiving device, there is known a device including: a light emitting element; a light receiving element; a base, housing the light emitting element and the light receiving element and having an opening; a light transmitting member, mounted on the opening of the base; and a light blocking member, disposed between the light emitting element and the light receiving element (see, for example, Patent Document 1).
Patent Document 1: Japanese Published Unexamined Patent Application No. 2001-61796